Now European astronomers have continued the run of discoveries of smaller
planets with the discovery of a trio of "super-Earths" rotating around
the star HD 40307, located 42 light-years from Earth towards the southern
Doradus and Pictor constellations. The new planets have masses of 4.2,
6.7, and 9.4 times the mass of Earth and orbits of 4.3, 9.6, and 20.4 days
respectively.

The star they orbit is a normal star, approximately the same size as our
sun. According to Didier Queloz and Michel Mayor, expert planet hunters
who led the discovery team, the planets are too hot to support life as we know
it.

However, despite this slight disappointment, the discovery raises the
intriguing possibility of a so-called "crowded universe" teeming with
undiscovered planets. HD 40307 was long thought to hold no planets -- it
is clear now that the discovery was only possible with the advances in
detection. There are likely many smaller planets that have yet to be
detected. In total 270 extrasolar planets have already been found.

Stéphane Udry, a colleague of Mayor, describes the advance stating, "With
the advent of much more precise instruments such as the HARPS spectrograph on
ESO's 3.6-m telescope at La Silla, we can now discover smaller planets, with
masses between 2 and 10 times the Earth's mass."

Mayor who works at the Geneva Observatory states, "Does every single star
harbour planets and, if yes, how many? We may not yet know the answer but
we are making huge progress towards it. Clearly these planets are only
the tip of the iceberg. The analysis of all the stars studied with HARPS
shows that about one third of all solar-like stars have either super-Earth or
Neptune-like planets with orbital periods shorter than 50 days."

quote: You would need to find a second case other than Earth to support your statement.

Why?

If the universe is infinite (or really, really, amazingly huge), then if Earth exists with intelligent life, obviously the probability is greater than zero.

Beyond that, if Mars had just a little more mass, and therefore managed to keep more of its atmosphere, it would've been conducive to life. There is liquid water under the surface of Europe, so there's a shot there. Thats one winner for life, and two close-calls, in one solar system.

With a probability greater than zero and an infinite universe, logic dictates there must be countless other Earth-like planets.

If you take a look at any of the pictures of distant galaxy clusters from a telescope like Hubble, and realize that almost everything in the image is a galaxy, and that thus you're looking at perhaps trillions of trillions of stars in just a tiny sliver of the sky.. Is it really all that hard to figure out that somewhere out there some other species developed an opposable thumb or equivalent?

quote: If the universe is infinite (or really, really, amazingly huge), then if Earth exists with intelligent life, obviously the probability is greater than zero.

The question is "What is the probability of there being life other than on Earth?". Obviously, if the question is "What is the probability of life existing in the universe?", that probability would be 1, because we know that life does exist. It is currently impossible to express a probability for the existance of life other than on Earth because we don't know of any other examples. It's similar to asking what is the probability of pulling a blue marble out of a bag, where you have no idea what color marbles are in the bag.

quote: Thats one winner for life, and two close-calls, in one solar system.

How exactly do you define "close-calls"? We haven't even been able to replicate abiogenesis under presumably ideal conditions in a controlled laboratory setting. What evidence do you have to suggest that life was just about to evolve on Mars and Europa but didn't quite make it?

quote: We can't possibly be that special; to even think we could be almost seems arrogant.

The universe doesn't care about what may or may not be "special" to humans. If it happened once, it happened once. If it happened a million times, it happened a million times. This weird sort of self-confidence issue that a lot of people have regarding the Earth's place in the universe is strange to me.

You can't just selectively exclude earth from a probability based on the universe when the earth is very clearly part of it.

quote: With a probability greater than zero and an infinite universe, logic dictates there must be countless other Earth-like planets.

I think there's something about that quote you must not understand.^

quote: Obviously, if the question is "What is the probability of life existing in the universe?", that probability would be 1

yes this is nit-picky but a probability of 1 is like saying: The Universe = EarthThe probability is actually 1*10^-(BIG NUMBER)... yes it is small, but it is greater than zero. As such, if you multiply that by an infinite universe, you have infinite other planets with life.

quote: It's similar to asking what is the probability of pulling a blue marble out of a bag, where you have no idea what color marbles are in the bag.

Well, considering we've pulled quite a few marbles out of the bag already and one of them was indeed blue (earth) how is it unreasonable to assume there could be more in the bag? Especially considering there's upwards of millions or billions of marbles in the bag?

He isn't discounting the Earth. He's saying Earth is reference point 1, find reference point number 2 before you start extrapolating data.

You're trying to debate on an emotional level based on your belief structure and you aren't comprehending the debate on a logical level. He's already said there could be millions of 'earths' out in the universe, he also said we could be the only one. We have no proof either way at this point.

> "We haven't even been able to replicate abiogenesis under presumably ideal conditions in a controlled laboratory setting"

I'm surprised you didn't sprain a finger when you typed the word "even" in that sentence. Once we've "replicated abiogenesis", we've created life itself. It's something that took nature billions of years and a laboratory the size of a planet (if not larger) to accomplish...and you're upset because we haven't been able to replicate that in our extremely limited experiments of the past 50 years or so?

The fact is, while we haven't replicated the entire process, we've made enormous strides in many areas. We've shown that inorganic molecules can spontaneously form into organic nucleotides -- not under "controlled laboratory conditions" but under conditions the primordial earth would have had. We've seen those nucleotides self-assemble into larger units, and likewise seen the spontaneous formation of protocells, which exhibit behavior remarkably similar to the simplest eukarotic life.

At our current rate of progress, within the next 250 years or so, we'll not only have replicated the entire process, but we'll be custom-building our own lifeforms, to whatever designs we wish.